[188922] in North American Network Operators' Group
Re: ASR-9K CPU troubleshooting
daemon@ATHENA.MIT.EDU (Andrey Slastenov)
Sun Apr 24 23:57:51 2016
X-Original-To: nanog@nanog.org
From: Andrey Slastenov <a.slastenov@gmail.com>
In-Reply-To: <CADy9NBCFivGb4TyPQ_bkJGRRQqWwDiUNuiWhz48gJk3SxHvfZQ@mail.gmail.com>
Date: Wed, 20 Apr 2016 10:00:32 +0300
To: Micah Croff <micahcroff@gmail.com>
Cc: NANOG <nanog@nanog.org>
Errors-To: nanog-bounces@nanog.org
You should check a log files during the time of high cpu load. ASR9K do most=
of the packet processing on NP.
High CPU load may happen during some control plane processing, like bgp neig=
hbor flapping.
=EF=D4=D0=D2=C1=D7=CC=C5=CE=CF =D3 iPhone
> 20 =C1=D0=D2. 2016 =C7., =D7 2:17, Micah Croff <micahcroff@gmail.com> =CE=C1=
=D0=C9=D3=C1=CC(=C1):
>=20
> I've experienced similar behavior on other platforms as well. Sometimes
> the output of the box is not correct. We were able to prove this to the
> vendor by conducting experiments and graphing the CPU. One of the
> protocols they said "couldn't possibly be causing this" turned out to be
> the root of the problem.
>=20
> I live by one rule when troubleshooting:
> The box is a lie.
>=20
> Micah
>=20
>=20
> On Tue, Apr 19, 2016 at 4:06 PM, Laurent Dumont <admin@coldnorthadmin.com>=
> wrote:
>=20
>> It coincides with nothing else? More traffic? CPU increasing at regular
>> intervals every day without any obvious reasons is probably something wor=
th
>> looking into!
>>=20
>>> On 4/18/2016 2:14 PM, Scott Weeks wrote:
>>>=20
>>>=20
>>> --- regezos@gmail.com wrote:
>>> From: Rukka Pal <regezos@gmail.com>
>>>=20
>>> How do you guys troubleshoot high CPU utilization on the ASR-9K platform=
?
>>> Detailed guides are available for IOS platforms, but I can't seem to fin=
d
>>> anything useful for the ASR.
>>>=20
>>> The average line-card (0/0/CPU0: A9K-24x10GE-TR) CPU utilization of my
>>> routers is about 10%, however recently I have noticed that 3-5 times a d=
ay
>>> it increases to 40% and stays there for about an hour (20% spp + 10% net=
io
>>> + the rest).
>>>=20
>>> I know this is well withing the acceptable range, but I am the kind of
>>> person who likes to understand every change in his network and during th=
e
>>> investigation I had to realize that I simply don't have the tools to
>>> troubleshoot the ASR CPU.
>>> -----------------------------------
>>>=20
>>>=20
>>> On cisco: sho proc cpu
>>>=20
>>> scott
>>=20
>>=20
